Meanwhile, the population of mosquitoes can be reduced by destroying their breeding sites such as containers with water, area with stagnant water, and even swamps with shallow water. In connection to this, larvicides can be used to annihilate the possible mosquito eggs in the breeding site under suspicion. As well, the commonly utilized larvicides are made of biological organisms such as Bacillus sphaericus and Bacillus thuringiensis that are being applied in line with methoprene products that contain biochemicals that hinder the maturation of mosquitoes (Pratt and Moore, 1993).
For adult mosquito control, the pyrethroid or organophosphate formulations, as approved by the United States Environmental Protection Agency, EPA, can be applied without serious health risk (Pratt and Moore, 1993). Although aerial application has been infrequently associated with breathing difficulties and irritation of the skin and the eyes, organophosphate triggers cholinesterase productions in humans, which in turn result to bronchospasm, nausea, diarrhea, sweating, and vomiting (Pratt and Moore, 1993).
Likewise, pyrethroids exposure may lead to seizures, headache, pulmonary edema, abnormal facial sensation, irritability, dizziness, vomiting, and salivation (Pratt and Moore, 1993). In terms of mosquito repellents, DEET, which contains N,N-diethyl-3-methylbenzamide, is widely used in varied formulations (Pratt and Moore, 1993). As such, products with 10%–50% DEET are found to be effective mosquito-repelling agents while those with higher than 50% DEET concentration failed to showed further efficacy increase (Pratt and Moore, 1993).
Other EPA-approved repellents such as permethrin and citronella are available in the market but not as high with the DEET efficacy (Pratt and Moore, 1993). The polyprotein coded in the viral RNA genome is translated into seven nonstructural and three structural proteins, which are crucial in the assembly, release, and replication of WNV (Grinev et al. , 2008). Before, WNV perpetuated and propagated naturally through bird-mosquito transmission, nowadays infections were also seen in reptiles, mammals, and humans (Grinev et al., 2008).
Summary The West Nile virus epidemic was common in Africa, Europe, Middle East, and Asia from the time of its first detection in Uganda in 1937. It was only in 1999 when WNV reached the territorial entity of the United States. Similar to Malaria, WNV is a mosquito-borne viral disease that can be transmitted and cause epidemic. The transmission cycle of WNV occurs not only between birds and mosquitoes but as up to date transmission among reptiles and human-human transmission were observed.
Specifically, when a mosquito bite a bird infected with WNV, it will become infected, and after 10 to 14 days, the mosquito can transmit the diseased to birds or mammals including humans by biting or sucking the victim’s blood. Likewise, Humans can also transmit the WNV through transplanted organs, breast-feeding, and blood transfusion. Symptoms of WNV infection such as fatigue, motor abnormalities, and cognitive dysfunction were commonly observed among the patients for more than a month.
The WMV victims are generally given three days to two weeks incubation period. Whereas 80% of the infected patients are unlikely to show any sign of illness, 20% of infected patients are foreseen to develop mild influenza to neuroinvasive diseases. Though WNV symptoms vary among the victims, it is observed that a patient infected with the virus is likely to experience headache, fever, skin rashes, body aches, and swollen lymph glands. These symptoms usually last for few days and can possibly overcome the immune system without proper medication.
However, severe diseases such as meningitis, meningoencepha¬litis, and encephalitis associated with WNV can result to death; thus, WNV infections must be properly given medical attention. For instance, in cases where severe WNV is observed, the infected person may experience headache, neck stiffness, muscle weakness, high fever, stupor, cognitive dysfunction, coma, convulsions, tremors, and even paralysis. Moreover, severity of infections and death were observed on patients in the senescence period of life.